Structure for encapsulating articles with viscous compositions such as casting resins

ABSTRACT

In a structure for encapsulating articles with viscous compositions such as casting resins, the individual components such as a premixer, a metering pump, a check valve etc., which all are interconnected with each other by pipes or conduits, are embedded in a solid block member and the conduits are formed by channels provided directly in the material of the block member. Thus, i. a., mounting of the individual components as well as of the conduits is considerably facilitated and a uniform temperature level for all components may easily be warranted.

i United States Patent [1 1 Hiibers et al.

1 1 NOV. 11, 1975 STRUCTURE FOR ENCAPSULATING ARTICLES WITH VISCOUS COMPOSITIONS SUCH AS CASTING RESINS Inventors: Gerd-Jan Hiibers. No. 72; Wilhelm I-Ioltmann, Wehrstrasse. both of 4291 Suderwick. German Filedz Mar. 12, 1973 Appl. No.1 340,444

Foreign Application Priority Data Mar. 17. 1972 Germany 2212980 US. Cl. 259/4; 141/51; 141/283; 141/392; 259/27; 259/61; 259/113; 425/200 Int. Cl. BOIF 15/02; B65B 31/00 Field of Search 141/67. 83. 82. 95. l. 141/5. 7. 11, 46. 51. 69. 94.100.105.129. 131. 231. 256. 270. 284. 32 U. 367. 283. 98. 392; 137/269. 271: 222/227. 233-235; 425/200. 246. 261; 259/4. 27. 61. 113

References Cited UNITED STATES PATENTS Schercr 141/95 X 3.213.903 10/1965 Armstrong 141/82 3.259.462 7/1966 Anscherlik 141/1 X 3.621.892 ll/1971 Gillespie 141/51 X 3.693.836 9/1972 Eisner 141/67 X 3.774.655 11/1973 Trusselle 141/46 Primclr livuminer-Richard E. Aegerter Assistant Eta/nilwr-Frederick R. Schmidt Altar/1e Agent. or Fir/I1Lerner. David. Littenberg & Samuel [57] ABSTRACT In a structure for encapsulating articles with viscous compositions such as casting resins. the individual components such as a premixer. a metering pump. a check valve etc.. which all are interconnected with each other by pipes or conduits. are embedded in a solid block member and the conduits are formed by channels provided directly in the material of the block member. Thus. i. a.. mounting of the individual components as well as of the conduits is considerably facilitated and a uniform temperature level for all components may easily be warranted.

23 Claims. 5 Drawing Figures Patent Nov. 11,1975 Sheet1of4 3,918,687

H h l I I I .III III].

U.S. Patent Nov.11, 1975 Sheet3of4 3,918,687

Fig.4 227 STRUCTURE FOR ENCAPSULATING ARTICLES WITH VISCOUS COMPOSITIONS SUCH AS CASTING RESINS BACKGROUND OF THE INVENTION This invention generally relates to means for encapsulating or filling articles with viscous compositions such as casting resins, and in particular relates to a structure of this kind having individual components such as a premixer, a metering pump, a check valve etc., with all these components being respectively connected to each other.

In such structures, accordirTg to the prior art the individual components each are mounted separately, and freely extending conduits in the form of tube connections or flange connections are provided to connect the components with each other. Consequently, such structures of the prior art require a comparatively large space, and beyond that their connections are expensive and susceptible with regard to residual depositions. If a component that became defective is to be substituted by a new one, then comparatively cumbersome mounting work is involved. Also, components that are connected to each other, due to their location isolated from each other readily may assume temperatures differing comparatively far from each other so that the casting resin subsequently flowing through the individual components is exposed to considerable variations in temperature, such variations adversely affecting the behaviour of the casting resin so that, when the temperature falls below a certain limit the entire flowing process may be interrupted which may cause-an investigation at which point clogging occured and where accordingly the temperature shouldbe additionally raised.

It is therefore and object of this invention to impove a structure as mentioned before in such a manner that a more compact and yet simpler arrangement is achieved.

It is a further object of the invention that the mutual connections may be mounted more easily and at lower costs, simultaneously requiring less maintenance.

It is further object of the invention that defective components may be easily replaced.

It is a still further object of the invention that temperature differences prevailing between different components may be kept at a minimum.

It is a still further object of the invention to provide a structure allowing to detect possible defects in a particularly simple and rapid manner. The components themselves are intended to have a particularly simple and clear configuration, permitting a handling of the filling material to be treated in precise a manner as possible, and finally ensuring a reliable operation.

SUMMARY OF THE INVENTION In accordance with the present invention, a structure for encapsulating articles with viscous compositions such as casting resins comprises a plurality of components such as a premixer, a metering pump, a check valve, a final or flow-type mixer etc., conduits for properly connecting these components with each other, and at least one of these components is embedded into the interior of a substantially solid block member, the conduits being constituted by channels provided directly in the material of the block member.

The individual components may then be formed as modules having a simple, preferably block-like configuration, and these modules may be fitted sealingly into recesses of similar configurations so that a releasable connection to adjacent conduits is automatically established.

Additional conduits or ducts may be provided in the material of the solid block member such ducts connecting with critical points of the structure and leading to the outer surface of the block member so that suitable instruments such as a manometer or a vacuummeter may be provided in order to guard such critical points. Also, reservoirs etc. may be connected through such ducts in order to supply the structure with auxiliary compositions.

The block member may be made of a material being a good thermal conductor in order to equalize different temperatures prevailing in the different components.

A plate-like cover member may extend over one major surface of the block member so that upon removal of that cover member all components are readily accessible.

Particularly, the flow-type mixer of the structure may have an elongated hollow space and a rigid rectangular plate extending in that hollow space, the rectangular plate having transverse apertures and being reciprocal in a direction transverse to its longitudinal direction. The hollow space of that flow-type mixer may be confined substantially by two parallel surfaces of two parallel metal plate members sealingly connected to each other. The hollow space has an upper inlet port and a lower outlet port for the viscous material flowing therethrough. Preferably in its center region the hollow space communicates with two major recesses and these recesses are closed by elastic diaphragms embracing between each other the rectangular plate. A piston rod connected to a crank shaft drive extends through the two diaphragms so that the rectangular plate may be reciprocated within the hollow space under the influence of the crank shaft drive, the two diaphragms serving as sealingly mounted supports. A particularly suitable embodiment of a metering pump as used in connection with the structure of this invention may have an upper pumping chamber connected to a reservoir and a lower check valve, and to the interior wall of the pumping chamber, at the end of the pumping chamber facing the reservoir, a gasket having an aperture may be rigidly secured so that the pumping piston may be formed as a prismatic or cylindrical body having a cross-section corresponding to the cross-section of the aperture, said pumping piston being sealingly insertable through the gasket and into the pumping chamber.

Preferably the entire structure with its outlet opening for the viscous composition communicates with the interior of a vacuum housing adapted to receive the articles to be encapsulated, the articles to be encapsulated being supported on a table reciprocal in longitudinal direction of the vacuum housing. The structure, with its outlet opening, may then also be reciprocal in a direction transverse to the longitudinal direction of the vacuum housing and substantially parallel to the major plane of the table supporting the articles to be encapsulated. This entails the appreciable advantage that the outlet opening of the structure may not only be approached to the individual articles but, when the structure is moved in the transverse direction, may also more or less uniformly distribute the viscous composition or, in particular, the casting resin over the surface of more extended, flat articles.

BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the invention. reference may be made to the preferred embodiments, exemplary of the invention, shown in the accompanying drawings, in which:

FIG. 1 schematically shows an elevational view of a structure as utilizing a block member in compliance with this invention;

FIG. 2 shows, partially in section, an elevational view of a preferred embodiment of a flow-type mixer as used in the structure of FIG. 1;

FIG. 3 is a side view of the rectangular mixing plate used in the mixer of FIG. 2 as an agitating means;

FIG. 4 shows a cross-section through a preferred embodiment of a metering pump as it is principally used in the structure of FIG. 1; and

FIG. 5 schematically shows an elevational view of the structure of FIG. 1 when utilized in connection with a vacuum container adapted to receive the articles to be encapsulated.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to FIG. 1 of the drawings, there is shown a structure according to the invention and generallydesignated with 10, for encapsulating articles with casting resins or similar viscous compositions. This structure comprises a solid block member .12 preferably made of a material such as aluminum exhibiting good thermal conductivity. In the embodiment here described, in the left upper region of block member 12 there is provided a premixer 14 which feeds a metering pump 16the outlet of which is coupled to a check valve 18 which in turn is connected to one inlet of an end mixer or flow-type mixer generally designated with 20. The outlet of the flow-type mixer 20 is connected with the inlet of a filling valve 21 through which the casting resin jet comprising the casting composition prepared in the desired manner may be directed toward the articles to be encapsulated (cf. in this connection FIG. 5).

Arranged in parallel with the functional group premixer 14, metering pump 16 and check valve 18 there is a similar functional group comprising a premixer 14, a metering pump 16 and a check valve 18' and likewise received by the block member 12 as indicated with the dashed lines. The outlet of check valve 18 similarly as the outlet ofcheck valve 18 is connected to the other inlet of the flow-type mixer 20 (via conduit 22c) so that the flow-type mixer may mix the two different constituents with each other as prepared in the respective premixers l4 and 14.

In order'to connect the premixer 14 with metering pump 16 there is provided a conduit 22a whereas for connecting metering pump 16 with the check valve 18 and for connecting the mixer 20 with the check valve 18 there are provided conduits 22b and 22c, respectively. These conduits 22 are directly worked out of the material of the solid block member in the form of channels so that separate, freely extending tubular conduits and similarly flange joints are eliminated, and simultaneously a good thermal transfer from the conduits 22 to the remaining components is ensured.

A piston rod 24a extends into metering pump 16, and the upper end of that piston rod 24a is connected to a yoke 26 which may be reciprocated by an actuating cylinder 25. Yoke 26 connects the upper end of piston rod 24a with the upper end of a corresponding piston rod 24 a which in a similar manner extends into metering pump 16 indicated only in phantom lines. Piston rods 24a and 24'a, respectively, readily may be substi- I pressure tight guidance of piston rod 24a (24a).'The design and the function of that metering pump 16 will a be set forth in greater detail further below in connec tion with FIG. 4.

To the upper end of premixer 14 there is connected a vacuum duct 30 by means of which a vacuum is. ap' plied to premixer, 14 in order todegas the filling composition situated within premixer l4. Into the lower end i of premixer 14 there terminates a composition supply duct 32 through which the filling material may be supplied from the outside of block member 12 into the pre-- mixer. The continuous flow-type mixer 20 has a mixing member 34 connected by means of a stud or a support member 35 between two diaphragms 36 and 36', re-v spectively. The mixing member 34 is positionedwithin i a recess 38 having a larger diameter than the mixing member 34so that the mixing member 34 may be re-, ciprocated within recess 38 in a direction transverse to its longitudinal or axial direction. A crank drive 40 which may be secured to the outer surface of block member 12 serves to generate the reciprocal motion. The elastic diaphragms 36, 36' are fastened to. the block member 12 by means of flange members 42 and 42, respectively, with the flange members 42, 42 being received in chambers 44 44 provided in the block member 12. Design and function of the flow-type mixer 20 will be discussed in greater detail in connection with FIG. 2 and 3.

The entire block member into which the individual components may be embedded, preferably may be of block-like geometry so that its front face extending in the plane of the drawing is constituted by an even sur I face. Thus, the front face readily may be covered by a cover plate 46 which, for instance, may be fastened in a foldable manner to the block member 12 by meansof hinges 48 similarly as the door of a cabinet. The cover plate 46 sealingly engages the adjacent surface of block member 12 so that for example thehollow space of premixer 14 may be closed off directly by means of cover plate 46. The same holds true with respect to conduits 22 etc..

Thus, there is the possibility by simply opening covering plate 46 to immediately have access to the several components and to examine whether or not the structure according to the invention functions properly.

Preferably, the cover plate, at least in those portions extending above components, is made of transparent material so that the operation of the components may also be controlled upon closure of the cover plate 46.

However, the cover plate likewise may be made completly of transparent material such as sufficiently'rigid plexiglass (R). Similarly, the cover plate may exhibit individual window-like lids associated. to the. respective components, and these lids may be opened individually I giving access to selected components only.

A stirrer 52 may be positioned within the interior of premixer 14 to counteract against possible sedimentation of the composition deposited in the hollow space of premixer 14. A duct 54 may be connected to the lower portion of premixer 14 connecting with a thermometer 54a so that the temperature of the casting resin as present in the premixer may be continuously controlled. Similarly, a duct 56 may connect conduit 22b-which in turn connects metering pump 16 and check valve 18 with each other which leads in the same manner as duct 54 to the periphery of the block member 12 to there terminate into a manometer 56a so that the pressure prevailing in conduit 22b may be controlled continuously in response to the pumping stroke. By means of manometer 56a significant conclusions with respect to the metering accuracy of the pump 16 may be drawn, and thus the proper operation of the entire structure may be judged. For appropriate function, a predetermined underpressure during the interval when the metering pump 16 sucks the composition in, and a predetermined overpressure are representative or typical, when the pump exhausts. In the event that the required values are not reached it is immediately detectable that the pump does not operate properly. In case the subpressure is not reached, either gasket or collar 27 or check valve 18, respectively, are defective, possibly due to contamination or the deposition of foreign matter such as impurities. In case the necessary overpressure is not attained the sealing gasket of the metering pump does not function properly. In case the necessary overpressure is even exceeded then either the filling valve 21 or the subsequent bore for feeding the composition are clogged or viscosity of the composition to be conveyed is too high which may be compensated for by increasing the temperature of the composition. Manometer 56a may similarly as other instruments of the structure according to the invention be equipped with endor limiting switches 128 initiating an alarm signal 126 when a predetermined value is exceeded or is not reached, respectively.

A duct 58 may lead from conduit 22c which connects check valve 18 with the flow-type mixer to the periphery of block member 12 and there communicate at its outer end via a valve 58a witha container 58b holding a rinsing composition. If clogging in the conduit 22c or the flow-type mixer has occurred, by means of opening valve 58a rinsing material may be readily applied in order to remove the clogging or the impurities.

To the lower end of recess 38 of mixer 20 there may likewise by connected ducts 60 and 62, respectively, which at their outer ends terminate into a thermometer 60a and a manometer 62a, respectively, so that the casting temperature and the casting presssure may be kept under immediate and continuous control.

The hollow space 64 of the premixer 14 may be formed as a direct recess in block member 12 so that a separate container for the premixer 14 may be omitted. For receiving metering pump 16 within block member 12 a recess 66a may be provided and metering pump 16 is then formed in a module-like manner then preferably having a block-like configuration. The contours of recess 66a correspond to the outer surfaces of the block form of metering pump 16 so that the module constituting metering pump 16 readily may be fitted into recess 16a. The horizontal front faces of recess 66a which are immediately contiguous to conduits 22a and 22b, re-

spectively, are flat and even and extend parallel with regard to the neighbouring surfaces of metering pump 16, so that O-ring seals 68 inserted into respective grooves 70 provided in the front faces of metering pump 16 may sealingly engage the respective surfaces of recess 66a with bias so that the metering pump 16 is connected to conduits 22a and 22b, respectively, in a pressure tight manner.

The hollow space 64 may communicate with an overflow duct 72 through which the composition supplied through supply duct 32 may be continuously fed back through line 220 so that the composition within premixer 14 may be kept in a continuous circulation this reducing problems of sedimentation as they may arise in connection with the use of casting resins of greater viscosity, regardless of the action of stirrer 52.

The entire block member structure may be equipped with a heating arrangement 222 so that the components may be kept at a temperature entailing a suitable viscosity of the constituents. The heating may be effective for the entire block member 12 or it may be subdivided into partial heatings each generating independently a constant temperature and these partial heatings may be activated as desired so that individual components may be subjected to a temperature particularly suitable for them.

Due to the modular design of the entire structure according to the invention itself a plurality of such structures may be combined to a greater entity or connected in parallel in order to increase the overall capacity.

FIG. 2 in greater detail shows the construction of a slightly modified embodiment of a flow-type mixer as employed in connection with this invention and as represented in FIG. 1 as element 20. Two plate members 101 and 102 are of similar geometry insofar as either one along one surface is provided with a recess 101a and 102a, respectively, these recesses extending over the major portion of the associated surface. At the upper ends of recesses 101a and 102a there are bores 1011) and 102b, respectively, whereas in the central area there is provided a major bore 101C and 102C, respectively. At the end of recess 101a remote from bore l01b plate member 101 is provided with a lower bore 101d communicating with recess 101a. Both plate members 101 and 102 in their corner areas are tightly secured to each other by means of bolts 103. Between plate members 101, 102 there extends within a groove 102d of plate member 102 an O-ring seal 104.

Bores 101c and 102C in outward direction terminate into an extension of larger diameter into which a flange ring 105 and 106, respectively, is inserted there being held in its position by means of bolts 107 and 108, respectively. Between either one of these flange rings 105, 106 and the associated plate member 101, 102 there extends a resilient diaphragm 109 and 110, respectively, and an O-ring seal 111 and 112, respectively, may here likewise be provided.

Recesses 101a and 102a thus, in combination, form an elongated hollow space 113 substantially defined by the two base planes of recesses 101a and 102a which extend parallel with regard to each other. Into this hollow space, a rectangular plate 114 is inserted in such a manner that its lateral surfaces 114a and 114b, repectively, merely leave a small distance from the base planes of recesses 101a and 102a.

As illustrated in FIG. 2, rectangular plate 114 is provided with a multitude of transverse bores 114e, whereas in its center area there are bosses 115 and 116,

respectively, on both sides. A bolt 117 extends through plate 114, the. two bosses 115 and 116 as well as through diaphragms 109 and 110. Adjacent the outer surfaces of diaphragms 109 and 110, a disc 123 and 124, respectively, is seated on bolt 117. A nut 122 is screwed onto the free end of bolt 117. The second end of the bolt is firmly connected to a bifurcated head 121 to which the other end of a piston rod 120 is pivotally linked, the other end of which is connected to a crank member 118 of a motor 119 rigidly connected to plate member 101.

The compositions to be intermixed with each other are conveyed into hollow space 113 through bores 1011a and 102b, respectively, flowing from there to outlet bore 101d. By means of the crank member 118 rectangular plate 114 is reciprocated so that it periodically almost touches the base planes of recesses 101a and 102a, respectively, in an alternating manner.

This end mixer or continuous flow-type mixer in particular is also adapted to mix smaller amounts of casting material. Plate members 101 and 102 may be provided with an additional channel system through which a heating means such as heated oil is circulated. Basi cally the flow-type mixer of FIG. 2 of course may be employed in an advantageous manner independently of the structure of FIG. 1.

Hereinafter, in connection with FIG. 4, in greater detail a metering pump is described as it is designated in FIG. 1 generally with 16; the metering pump of FIG. 4 which there is designated generally with 210 is designed as a component that my be employed independently of the structure of FIG. 1.

The metering pump 210 of FIG. 4 includes a reservoir 212 closed off at its upper side by a cover plate 214. At its lower end the reservoir 212 terminates into a metering chamber 216 the lower end of which is connected to a check valve 218. The check valve 218 of FIG. 4 corresponds to the check valve 18 of FIG. 1. Similarly, reservoir 212 corresponds to the hollow space 64 of FIG. 1. A piston rod 220 (corresponding to piston rod 24a of FIG. 1) sealingly extends through cover plate 214. A pumping piston 222 is provided at the lower end of piston rod 220. At the upper end of chamber 216, there is a disc-like gasket 224 (comparing with collar 27 of FIG. 1) the height of which covers only a fraction of the height of metering chamber 216 so that sufficient volume remains for receiving filling material to be forced out by pumping piston 222. Along its periphery gasket 224 is sealingly connected to the interior wall of metering chamber 216. Gasket 224 is provided with an aperture 225 whose cross-section just corresponds to the cross-section of pumping piston 222. Gasket 224 preferably is made of sufficiently resilient material so that piston 222 may enter aperture 225 at a certain bias so that gasket 224 sealingly encloses pumping piston 222 thus preventing a further exchange of filling material between the hollow space of reservoir 212 and the hollow space of metering chamber 216. At the upper end of cover plate 214 a scale 226 may be provided cooperating with a pointer 227 affixed to piston rod so that the respective height position of the pumping piston 222 may be indicated.

The flowable filling material 228 such as casting resin or a thixotropic liquid is received within the interior of reservoir 212, and preferably a certain underpressure acts upon the filling material 228 within the reservoir.

If pumping piston 222 is positioned as shown in FIG. 4 when the filling material 228 may enter through aperture 225 into the metering chamber 216. Upon loweringpu'mping piston 222 sealingly enters aperture 225 so that further filling material 228 may not flow from reservoir 212 into the metering chamber 216. Likewise, filling material already fed into the metering chamber 216 is no more capable to escape from cham- I ber 216 through aperture 225. ,With respective lowering of pumping piston 222 and the subsequent forced shifting of the filling material present in chamber 216 there remains the only possibility for the filling material to escape through check valve 218. Through check.

valve 218 exactly that amount of filling material is forced out which equals that portion of the pumpingcheck valve 18 of FIG. 1 and hollow space 64 of FIG.(

1 it is possible to meter minute amounts of filling material at very great accuracy even though metering of greater amounts may be carried out in just a simple manner because except for pumping piston 222 there are no movable parts nor narrow cross-sections which might adversely affect the metering accuracy. Rather, it is always warranted that exactly that amount of filling material leaves chamber 216 which equals the volume portion of pumping piston 222 introduced into chamber 216. Beyond that, there is the aforementioned advantage that pumping piston 222 may be replaced by another pumping piston of greater or smaller diameter (together with an associated gasket 224) so that the pumping volume for the same stroke may be varied as a required.

Thus, in contrast to known so-called plunger pumps, it is not necessary to provide for a proper sealing be tween the pump piston and the interior surface of the pump chamber, which would entailconsiderable difficulties anyway at least in connection with handling viscous filling materials. It is merely required that gasket 224 properly engages pumping piston 222 when moved in downward direction into chamber 216. Gasket 224 then is not allowed to escape in axial direction because in that case displacement of filling material contained in chamber 216 into areas other than of the check valve, possibly an undesired change of the measuring volume might occur. Therefore, depending on the requirements to be expected, at least the upper surface of the gasket 224 which preferably is made of resilient material may be covered by a supporting disc 224a made for example of sheet metal. Similarly, such a supporting disc 224b may be provided at the lower surface,

of gasket 224 in order to definitely prevent a deformation of gasket 224 when pumping piston 222 is introduced into aperture 225.

In practice, a metering pump 2111 according to FIG.

4 or a metering pump l6 according to FIG. 1 has proved as being particularly suitable for exactly meter- 9 spective field in which the metering pump is to be employed, near gasket 224 a guide ring 230 fixedly attached to the interior wall of reservoir 212 by means of a support 232 may surround piston rod 220.

In order to facilitate displacement of filling materials exhibiting a higher viscosity, in particular sitations a gas pressure may be exerted onto the surface of the filling material to assist the displacement of the filling material through the check valve. In situations even more critical a piston actuated for example mechanically and adjusted with its surface to the surface of the filling material and sealingly engaging the interior wall of reservoir 212 may exert a constant pressure onto the filling material.

FIG. diagrammatically illustrates how the structure of FIG. 1 may cooperate with a vacuum housing generally designated 180 maintained under vacuum by means of vacuum pump 124, through line 130. At its upper side vacuum housing 180 is closed off by an upper plate 182, and a threaded spindle 184 extends through the interior of vacuum housing 180 in longitudinal direction thereof. With respect to the drawing, the right end of spindle 184 is connected to a hand wheel 186 through which the spindle may be rotated manually. By means of threaded bearings 190 a receiving table 188 upon which the articles to be encapsulated may be supported is coupled to spindle 184. Spindle 184 is supported rotatably in the lateral walls of vacuum housing 180 by means of suitable bearings. Articles to be encapsulated with casting resin orthe like and deposited upon receiving table 188 thus may be moved in direction of spindle 184 with respect to the filling opening or outlet opening 204 of structure 10 (comparing with filling valve 21 of FIG. 1).

A slide surface 192 is provided at the upper face of upper plate 182, and that slide surface 192 is engaged by a slide plate 194 mounted to structure 10. A guide rail.l96 having an L-shaped cross-section as shown in FIG. 5 guides slide plate 194 in a direction perpendicular with regard to the plane of the drawing. A shaft 198 extends in a direction normal with regard to the surface of upper plate 182 besides the edge of slide plate 194 remote from guide rail 196. That shaft 198 is rotatably supported in upper plate 182, and its upper end terminates into a swivel 202 whereas near the slide plate 194 a gear 200 is seated on shaft 198. Gear 200 meshes with a rack extending along the edge of slide plate 194 facing gear 200. In this manner, it is possible to move structure 10 together with the associated filling opening or outlet opening 204 in a direction transverse with regard to the longitudinal axis of spindle 184. This entails the considerable advantage that the filling jet leaving outlet opening 204 may be applied to the article to be encapsulated and deposited below opening 204 not only in a pointlike manner but also along a line, that is by actuating swivel 202 so that structure 10 is moved parallel with regard to the article to be treated, and consequently a very uniform supply of the casting resin to the article positioned therebelow is ensured also in case the article is of comparatively elongated configuration. Basically, the motion in transverse direction may be coupled in proportion to the amount of casting resin discharge so that there is a predetermined ratio between the supplied amount of casting resin and the distance through which opening 204 is moved on.

What we claim is:

1. A structure for use in encapsulating articles with viscous compositions, comprising, in combination, a

solid base member formed of a metal exhibiting good thermal conductivity and having a plurality of recesses therein in which are embedded a pre-mixer for receiving and pre-mixing viscous material, a metering pump connected to said pre-mixer, a check valve connected to said metering pump, and a continuous flow-type mixer connected to said check valve, said pre-mixcr, metering pump, check valve, and continuous flow-type mixer being formed as components comprising blocklike modules, said components being fitted releasably into said recesses, said recesses having substantially the same contours as said block-like modules, said solid base member having additionally embedded therein a plurality of channels including viscous material inlet means connected to said pre-mixer, premixer outlet conduit means connecting said pre-mixer to said metering pump, metering pump outlet conduit means connecting said metering pump to said check valve, and check valve outlet conduit means connecting said check valve to said continuous flow-type mixer, said continuous flow-type mixer further including an outlet opening for viscous compositions.

2. A structure as claimed in claim 1, in which the channels terminate in plane front faces of said recesses, said block-Like components including O-ring seals en-' gaging these front faces in a pressure tight manner.

3. A structure as claimed in claim 1, in which the premixer comprises a hollow space in said solid base member.

4. A structure as claimed in claim 3, in which said metering pump comprises a filling chamber and a piston rod having a lower portion and an upper portion, the lower portion of said piston rod extending into said filling chamber and the upper portion of said piston rod extending beyond an upper end of said metering pump through the hollow space of said premixer and beyond the periphery of said solid base member, a reciprocat-' ing drive means for driving said piston rod, said reciprocating drive means being coupled to the free end of said piston rod extending beyond said solid block-like body member.

5. A structure as claimed in claim 3, in which an overflow duct is connected to the hollow space of said premixer, said overflow duct cooperating with a supply duct connected to a lower region of said premixer.

6. A structure as claimed in claim I, in which an additional channel is formed by a duct connected to said conduit extending between said check valve and said continuous flow-type mixer, the outer end of said duct communicating via a valve with a container containing a rinsing composition.

7. A structure as claimed in claim 1, in which said solid base member is made of aluminum.

8. A structure as claimed in claim 1, further comprising heating means associated with said solid base member.

9. A structure as claimed in claim 8, wherein said heating means is subdivided into'a plurality of individual heating elements, said heating elements being associated with different areas of said structure.

10. A structure as defined in claim 1, further comprising a cover plate means made of transparent material, said cover plate means having an inner face and an outer face, said cover plate means closing off said solid base member at least partially in regions in which said components are inserted into said recesses of said solid base member, the inner surfaces of said cover plate means sealingly engaging the hollow spaces of said 1 1 components positioned therebelow.

11. A structure as claimed in claim 10, wherein said cover plate means are integral with a cover plate releasably secured to said solid base member.

12. A structure as claimed in claim 11, wherein the entire covver plate is formed as a plate-Like member made of transparent material.

13. A structure as claimed in claim 11, wherein said cover plate means is linked to said solid base member by means of hinge means in a cabinet doorlike manner.

14. A structure as defined in claim 1, wherein said continuous flow-type mixer comprises an elongated hollow space defined by a pair of plate members extending parallel to each other and being sealingly connected to each other except for said hollow space, and a rigid plate extending longitudinally within said hollow space, said rigid plate being capable of transverse reciprocation within said hollow space, and said rigid plate a plurality of transverse bores, said hollow space communicating with at least one inlet and at least one outlet, said hollow space further communicating with a central bore provided in said plate members, said central bore being sealed by a pair of resilient diaphragm means disposed transversely to said bore'and on either side of said rigid plate, and including connecting means extending through said diaphragm means and said rigid plate, to connect said rigid plate to a drive means positioned externally of said hollow space and capable of transversely reciprocating said plate.

15. A structure as claimed in claim 14, wherein the longitudinal direction of said hollow space extends substantially in'a vertical direction and wherein said inlet is at the upper end of said plate members, whereas said outlet is at the lower end of said plate members.

16. A structure as claimed in claim 14, wherein the distance of said diaphragm from the central plane of said hollow space is larger than the distance of the defining surface of the plate member from said central plane.

17. A structure as claimed in claim 14, wherein the gap between the plate and the neighbouring defining surfaces of said plate members is less than the thickness of said plate.

12 r 18. A structure asclaimed in claim 14, wherein said plate members are provided with channels for conducting a cooling means or a heating means, respectively.

19. A structure as defined in claim 1, whereinsaid metering pump comprises a metering chamber, said metering chamber including an inlet portion and an outlet portion, said inlet portion associated withsaid pre-mixer and said outlet portion associated with said check valve, an annular gasket being sealingly con nected to the inner wall of said metering chamber, said annular gasket being associated with said inlet portion of said metering chamber, a pumping piston for said metering pump, said pumping piston having acrosssection corresponding to the cross-section of the aper ture in said annular gasket and means for reciprocating said piston within said metering chamber so that said piston may be withdrawn from said metering chamber upon its withdrawal from the aperture in said annularv gasket.

20. A structure as defined in claim 19 wherein said annular gasket is made of resilient materials, sothat said aperture may receive said piston with bias, and

wherein both surfaces of said annular gasket are covered by annular disks of rigid, non resilient material.

21. A structure as defined in claim 19, wherein said pumping piston includes a piston rod sealingly guided through said pre-mixer, and including a guide, ring mounted within said pre-mixer, for guiding said piston rod upon its reciprocation toward said annular gasket. 1 22. A structure as defined in claim 21, further comported mounted within said vacuum housing, and. v

means for moving said solid base member including said outlet opening in a direction transverse to said vacuum housing and along a plane extending substantially parallel to the plane of said receiving table.

UMIED STATES PATENT OFFICE CERTIFICATE OF CORRECTlON Patent No. 3,918,687 Dated November 11, 1975 GerdJan Hubers, Wilhelm Holtmann It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 5, line 67, the number "16a" should read 66a Column 11, line 6, the word covver" should read cover Column 11, line'l9, after "plate" insert including Signed and Sealed this Attest:

RUTH C. MASON I C. MARSHALL DANN A trestmg Officer Commissioner oflatems and Trademarks 

1. A structure for use in encapsulating articles with viscous compositions, comprising, in combination, a solid base member formed of a metal exhibiting good thermal conductivity and having a plurality of recesses therein in which are embedded a pre-mixer for receiving and pre-mixing viscous material, a metering pump connected to said pre-mixer, a check valve connected to said metering pump, and a continuous flow-type mixer connected to said check valve, said pre-mixer, metering pump, check valve, and continuous flow-type mixer being formed as components comprising block-like modules, said components being fitted releasably into said recesses, said recesses having substantially the same contours as said block-like modules, said solid base member having additionally embedded therein a plurality of channels including viscous material inlet means connected to said premixer, premixer outlet conduit means connecting said pre-mixer to said metering pump, metering pump outlet conduit means connecting said metering pump to said check valve, and check valve outlet conduit means connecting said check valve to said continuous flow-type mixer, said continuous flow-type mixer further including an outlet opening for viscous compositions.
 2. A structure as claimed in claim 1, in which the channels terminate in plane front faces of said recesses, said block-Like components including O-ring seals engaging these front faces in a pressure tight manner.
 3. A structure as claimed in claim 1, in which the premixer comprises a hollow space in said solid base member.
 4. A structure as claimed in claim 3, in which said metering pump comprises a filling chamber and a piston rod having a lower portion and an upper portion, the lower portion of said piston rod extending into said filling chamber and the upper portion of said piston rod extending beyond an upper end of said metering pump through the hollow space of said premixer and beyond the periphery of said solid base member, a reciprocating drive means for driving said piston rod, said reciprocating drive means being coupled to the free end of said piston rod extending beyond said solid block-like body member.
 5. A structure as claimed in claim 3, in which an overflow duct is connected to the hollow space of said premixer, said overflow duct cooperating with a supply duct connected to a lower region of said premixer.
 6. A structure as claimed in claim 1, in which an additional channel is formed by a duct connected to said conduit extending between said check valve and said continuous flow-type mixer, the outer end of said duct communicating via a valve with a container containing a rinsing composition.
 7. A structure as claimed in claim 1, in which said solid base member is made of aluminum.
 8. A structure as claimed in claim 1, further comprising heating means associated with said solid base member.
 9. A structure as claimed in claim 8, wherein said heating means is subdivided into a plurality of individual heating elements, said heating elements being associated with different areas of said structure.
 10. A structure as defined in claim 1, further comprising a cover plate means made of transparent material, said cover plate means having an inner face and an outer face, said cover plate means closing off said solid base member at least partially in regions in which said components are inserted into said recesses of said solid base member, the inner surfaces of said cover plate means sealingly engaging the hollow spaces of said components positioned therebelow.
 11. A structure as claimed in claim 10, wherein said cover plate means are integral with a cover plate releasably secured to said solid base member.
 12. A structure as claimed in claim 11, wherein the entire covver plate is formed as a plate-Like member made of transparent material.
 13. A structure as claimed in claim 11, wherein said cover plate means is linked to said solid base member by means of hinge means in a cabinet doorlike manner.
 14. A structure as defined in claim 1, wherein said continuous flow-type mixer comprises an elongated hollow space defined by a pair of plate members extending parallel to each other and being sealingly connected to each other except for said hollow space, and a rigid plate extending longitudinally within said hollow space, said rigid plate being capable of transverse reciprocation within said hollow space, and said rigid plate a plurality of transverse bores, said hollow space communicating with at least one inlet and at least one outlet, said hollow space further communicating with a central bore provided in said plate members, said central bore being sealed by a pair of resilient diaphragm means disposed transversely to said bore and on either side of said rigid plate, and including connecting means extending through said diaphragm means and said rigid plate, to connect said rigid plate to a drive means positioned externally of said hollow space and capable of transversely reciprocating said plate.
 15. A structure as claimed in claim 14, wherein the longitudinal direction of said hollow space extends substantially in a vertical direction and wherein said inlet is at the upper end of said plate members, whereas said outlet is at the lower end of said plate members.
 16. A structure as claimed in claim 14, wherein the distance of said diaphragm from the central plane of said hollow space is larger than the distance of the defining surface of the plate member from said central plane.
 17. A structure as claimed in claim 14, wherein the gap between the plate and the neighbouring defining surfaces of said plate members is less than the thickness of said plate.
 18. A structure as claimed in claim 14, wherein said plate members are provided with channels for conducting a cooling means or a heating means, respectively.
 19. A structure as defined in claim 1, wherein said metering pump comprises a metering chamber, said metering chamber including an inlet portion and an outlet portion, said inlet portion associated with said pre-mixer and said outlet portion associated with said check valve, an annular gasket being sealingly connected to the inner wall of said metering chamber, said annular gasket being associated with said inlet portion of said metering chamber, a pumping piston for said metering pump, said pumping piston having a cross-section corresponding to the cross-section of the aperture in said annular gasket and means for reciprocating said piston within said metering chamber so that said piston may be withdrawn from said metering chamber upon its withdrawal from the aperture in said annular gasket.
 20. A structure as defined in claim 19 wherein said annular gasket is made of resilient materials, so that said aperture may receive said piston with bias, and wherein both surfaces of said annular gasket are covered by annular disks of rigid, non-resilient material.
 21. A structure as defined in claim 19, wherein said pumping piston includes a piston rod sealingly guided through said pre-mixer, and including a guide ring mounted witHin said pre-mixer, for guiding said piston rod upon its reciprocation toward said annular gasket.
 22. A structure as defined in claim 21, further comprising means for generating an over-pressure within said pre-mixer.
 23. A structure as defined in claim 1, including an outlet opening for said viscous composition, a vacuum housing including inlet means communicating with said outlet opening, a substantially planar receiving table upon which articles to be encapsulated may be supported mounted within said vacuum housing, and means for moving said solid base member including said outlet opening in a direction transverse to said vacuum housing and along a plane extending substantially parallel to the plane of said receiving table. 